Lactiplantibacillus plantarum CFS from Pulicaria jaubertii inhibits Aspergillus fumigatus and Candida albicans growth
Background
The escalating crisis of antifungal resistance necessitates the urgent discovery of novel therapeutic agents. Current antifungal treatments often face challenges such as limited efficacy, host toxicity, and high recurrence rates, particularly for prevalent infections like vulvovaginal candidiasis caused by Candida albicans and invasive aspergillosis from Aspergillus fumigatus. Natural reservoirs, especially bacteria isolated from medicinal plants, represent an underexploited source of biologically active compounds. This study explores the potential of postbiotic cell-free supernatants (CFS) from Lactiplantibacillus plantarum as a sustainable, multicomponent antifungal strategy to address these critical fungal challenges.
Study Design
Lactiplantibacillus plantarum was isolated from surface-sterilized leaves of the medicinal plant Pulicaria jaubertii and subsequently cultured to produce cell-free supernatants (CFS). The chemical composition of the CFS was characterized using Fourier-transform infrared (FT-IR) spectroscopy. Antifungal efficacy was then rigorously evaluated against clinically significant isolates of Aspergillus fumigatus and Candida albicans. Growth inhibition against A. fumigatus was assessed via an agar incorporation method, while C. albicans activity was determined using an agar well-diffusion assay. The study investigated dose-dependent effects, testing the CFS at concentrations up to 30% (v/v).
Results
The FT-IR spectroscopy analysis revealed that the Lactiplantibacillus plantarum CFS is a complex mixture, containing characteristic functional groups indicative of organic acids, peptides, and carbohydrates. This multicomponent supernatant exhibited potent, dose-dependent antifungal activity against both tested pathogens. > At a concentration of 30% (v/v), the CFS achieved a remarkable 71.9% growth inhibition against Aspergillus fumigatus and an even higher 90.0% growth inhibition against Candida albicans.
Key Findings
- L. plantarum CFS contains organic acids, peptides, and carbohydrates as identified by
FT-IR. - CFS inhibited A. fumigatus growth by 71.9% at 30% (v/v).
- CFS inhibited C. albicans growth by 90.0% at 30% (v/v).
- Antifungal efficacy was dose-dependent, with a sharp increase between 20% and 25% (v/v).
Why It Matters
The discovery of novel antifungal agents is critical given the rising rates of antifungal resistance and the limitations of existing therapies. This study highlights the significant potential of Lactiplantibacillus plantarum cell-free supernatant (CFS) as a natural, multicomponent postbiotic intervention. Integrating plant biodiversity with microbial chemistry offers a sustainable pathway for developing new antifungal strategies. While this is an in vitro preclinical finding, it lays foundational groundwork for future in vivo studies and potentially the development of topical or systemic antifungal formulations. The complex nature of the CFS, with its blend of organic acids, peptides, and carbohydrates, suggests a multi-mechanistic mode of action, which could be more resistant to the development of fungal resistance compared to single-target drugs. Further research is needed to isolate and identify the specific active compounds and to validate efficacy in animal models before any clinical translation.
antifungal
lactiplantibacillus plantarum
postbiotic
aspergillus fumigatus
candida albicans
in vitro